textproduct: Albany

WHAT HAS CHANGED

WPC Excessive Rainfall Outlook for today/tonight has a Slight Risk for our southeastern areas, although the Moderate Category is very close to Dutchess and Litchfield Counties. NBM and WPC QPF continue to show 1-3" of rainfall for southern areas, with some localized totals exceeding 3" possible across far southern Dutchess and Litchfield Counties.

Latest CAMs suggest the heaviest rainfall may be done by this evening and moving off to the east into New England, with drier conditions for our area for tonight. Will keep the Flood Watch in effect through Tuesday morning, but could potentially need to trim the end time back if the trends in CAMs continue.

KEY MESSAGES

1) Periods of showers and embedded thunderstorms, some with moderate to heavy rainfall, will continue across Ulster, Dutchess and Litchfield Counties through this evening. Isolated to scattered flash flooding is expected to occur, especially within urban and poor drainage areas.

2) Drier weather returns for the middle of the week with temperatures trending back above normal again later this week.

DISCUSSION

KEY MESSAGE 1...

The surface map continues to show a stationary boundary located over the mid Atlantic States, extending from central Ohio along the PA/MD border and towards northern Delaware and southern New Jersey. Although weak waves of low pressure will slide along this boundary, the front will likely remain stalled in place for today and into tonight.

Periods of showers have been ongoing across the far southern parts of the County Warning area since Sunday afternoon. There had been some embedded thunderstorms on Sunday evening, but most of the activity lately has not had thunder. Although the best convective elements are generally south of the area over eastern PA/NJ, there have been bursts of moderate rainfall at times. MRMS has been suggesting rainfall rates up to a third of an inch across southern Ulster County, although the more significant rainfall rates have not been far away across Orange County, where NYS Mesonet station at Otisville is suggesting has reported over five inches of rainfall since 9 pm last evening.

PWAT values were reported to be around 1.50" at the 00Z KALY sounding. KOKX showed a PWAT of 1.89" and guidance suggest values will reach up to around 2.00" across southern parts of the County Warning Area during the day today. The values across southern areas are about 150%-180% of normal, which is about 2 STD above normal. Model soundings are showing plenty of signs for excessive rainfall, including a moist profile throughout the column, skinny CAPE profile, high PWATs and a high freezing level, indicating the potential for warm-rain processes and efficient rainfall production.

Based off the latest CAMs, additional periods of showers will continue across southern areas through the day today. There is some question about the northern extent of the precip and some showers may get as far north as the Capital Region and I-90 for early this morning and then again later this afternoon. However, the moderate to heavy showers will remain in place over the southern 3 counties (Ulster, Dutchess and Litchfield). While there may be some heavier bursts with this ongoing activity for early this morning, another round of heavier showers is anticipated for this afternoon, based off the latest 3km HRRR. Within this rainfall, rates may exceed one inch per hour. This will result in the potential for flash flooding, especially within urban, poor drainage and low lying areas. Road closures due to flooding can be expected for parts of the Watch area.

Based off this, will keep the Flood Watch in place and will not need to extend any further north. WPC has also placed the southeastern Catskills, mid Hudson Valley, southern Berkshires and NW CT in a slight risk for excessive rainfall (level 2 of 4) for today, although the moderate area is very close to our County Warning area, just off to the south. Total rainfall amounts of 1 to 3 inches remain possible south of Albany through Tuesday with localized amounts in excess of 3 inches possible, especially where repeated rounds of heavy rain occur, such as far southern Dutchess and Litchfield Counties. The latest NBM shows pockets of 4-5" in those areas, which seems plausible at this time.

Based off the latest guidance, the steadiest showers may be ending this evening, as they slide off to the east into New England. This could allow for a drying trend for tonight. This could potentially allow us to end the Flash Flood Watch early, but will continue to evaluate more guidance and radar trends later today before making that decision.

KEY MESSAGE 2...

As the wave of low pressure along the stalled boundary exits off to the east on Tuesday, high pressure will be building into the region from the west. This should allow for drier and more quiet weather for Tuesday night through much of Thursday. Although the cloudy and cooler weather for early this week, there should be a return to warmer temperatures. Highs will be back into the 80s for Wednesday and Thursday, with the latest NBM guidance suggesting upper 80s possible in valley areas once again by Thursday. While heat index values appear to remain below advisory criteria, it will be a noticeable warmup. Despite the warmer weather, it should be fairly rain-free for Tuesday night through Thursday, although far northwestern areas could see a late day shower or thunderstorm for Thursday evening.

AVIATION /12Z MONDAY THROUGH FRIDAY/

A steady light to occasionally moderate rainfall has been impacting southern areas through the overnight hours, including KPOU. Based on CAMs and radar trends, additional periods of steady light to moderate rainfall will continue for KPOU with MVFR conditions into the morning hours. A period of IFR visibility is possible there during the early afternoon hours, with some embedded heavier bursts. Meanwhile, the other sites will be mainly dry, but can't rule out some passing showers at KALB and KPSF, with perhaps some additional MVFR visibility at KPSF. All sites will be seeing gradually lowering ceilings, so even outside of rain, MVFR cigs are expected at KALB and KPSF by late in the day. KGFL will continue to be dry with mainly VFR conditions. Some LLWS is possible for KPSF and KPOU during the day, with 2 kft winds around 35-40 kts from a southeasterly direction.

Rainfall will start to taper off for all sites this evening into early tonight. Flying conditions will likely still be MVFR for sites thanks to lingering low level moisture keeping low ceilings around, although KGFL should continue to be the exception and remain VFR. Surface winds will be light to calm for all sites tonight.

Outlook...

Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: No Operational Impact. NO SIG WX. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: High Operational Impact. Likely SHRA...TSRA. Friday Night: Moderate Operational Impact. Chance of SHRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...Flood Watch through Tuesday morning for CTZ001-013. NY...Flood Watch through Tuesday morning for NYZ063>066. MA...None. VT...None.